I know that it is something you stumble upon in most RPGs, but I'd say that you shouldn't think of Dirt, Grass and Water as "Random Pixel Patterns in Green, Brown and Blue."
If you're going to make a dirt pattern for example, what kind of dirt would it be? How would it look at the edges and is it dry or watery; Stony or dirty?
Same with the grass, try to define strands of grass; preferrably ones that stick up more or less.
And please make some transitions, because as it is now, it wouldn't trick me for a second if you hadn't put that character there.
But please, I'm not trying to disencourage you; Rather the opposite, I'm trying to make you find your hidden powers; Awaken your passion
.
Now I say rework it. Think it through; Make a pattern and then think of how it's all going to stick together. And What KIND of grass is it? Try to make that kind of grass. And what KIND of dirt is it? Imagine it as if you wanted to walk on it. Try to make that kind of dirt.
Water is hard so I'll just leave it up to you to experiment with it :}
